Hair conditioners are mainly intended to improve the combability of disturbed or weakened hair resulting from shampooing or chemical treatments, such as bleaching or permanent waving and straightening or weathering or natural causes. Hair straighteners usually are applied to hair having a tight curl, e.g., afro or negroid hair which is subject to spontaneous knotting by entanglement with neighboring hair shafts, resulting in high stress when combed.
Historically, temporary straightening of hair has been achieved by passing a heated metal comb through the hair with the aid of a pressing oil or cream. The oil acts as a heat conductor and lubricant so that the comb can slide through the hair without pulling and sticking. The pressing cream normally contains mineral oil, lanolin, wax, fatty alcohol, polyethylene glycol (PEG) stearate, etc. Additionally, semi-permanent straightening can be achieved by chemical hair straighteners presently on the market which are based on sodium hydroxide, lithium hydroxide, sulfite or thioglycolate, etc. The chemical hair straighteners break the disulfide bond of the hair to form a straight configuration either by relinking the disulfide bond or by forming a new covalent bond according to The Chemistry of Cosmetics and Manufacture by Maison G. deNavarre. Thus, these chemical hair straighteners react with hair, change the structure of the hair and finally straighten the hair for a period which lasts through many shampoos.
The disadvantages of the prior art hair relaxing or straightening compositions and procedures using harsh chemicals are irritation to scalp/skin due to the high pH (10-12) of the caustics or similar compounds; hair cuticle uplifting; extensive cuticle damage caused by the caustic; hair becomes dry and dull; sebum flow from scalp is reduced because of cuticle damage; and the structure in the hair is changed because many of the chemical bonds of the hair such as the disulfide bonds are broken and only some are reformed into new covalent bonds.
U.S. Pat. No. 4,530,830 has addressed the problem of the irritancy of the harsh chemicals used in the hair straightening compositions by using 2% to 20%, preferably 2.5% to 8%, by weight of a quaternary ammonium hydroxide as the straightening agent in place of the sodium hydroxide in an emulsion form in order to reduce the irritating tendency exhibited by some of the quaternary ammonium hydroxides at some use concentrations. The aqueous emulsion also contains 2-20% nonionic-emulsifier such as polyethylene glycol ether of cetyl or lauryl or lanolin alcohol, 2-30% of an emollient such as cetyl alcohol, stearyl alcohol, paraffin, mineral oil and lanolin alcohol, and optionally a humectant such as propylene glycol, glycerin, sorbitol or hexylene glycol. This composition is massaged into the hair, left on the hair for ten minutes, again massaged into the hair and washed completely out of the hair. The quaternary ammonium hydroxide straightening agent affects the chemical structure of the hair similarly to the sodium hydroxide and is unlike the present unique hair conditioner and straightener which provides good conditioning, but does not change any chemical structure in the hair.
In the field of hair conditioning, the prior art is replete with hair conditioning compositions containing one or more of the components of the present novel and unique hair conditioner -straightener compositions. For example, U.S. Pat. No. 4,275,055 discloses compositions containing a stearamidopropyldimethyl amine conditioning agent and U.S. Pat. Nos. 4,149,551 and No. 4,206,196 disclose conditioning articles having a di-higher alkyl dimethyl ammonium chloride or a fatty alcohol conditioning agent on a flexible substrate such as paper and the like. In U.S. Pat. Nos. 4,421,740 and 4,269,824, a composition is disclosed which employs the combination of di(hydrogenated tallow) dimethyl ammonium chloride, cetyl or stearyl alcohol and hydroxyethyl cellulose. U.S. Pat. No. 4,436,722 discloses the combination of distearyl dimethyl ammonium chloride, cetyl alcohol and propylene glycol in a hair conditioning compositions. U.S. Pat. Nos. 4,144,326 and 4,160,823 disclose similar compositions which include the combination of distearyl dimethyl ammonium chloride and propylene glycol; and U.S. Pat. No. 4,183,917 discloses a hair conditioner composition which comprises the combination of distearyl dimethyl ammonium chloride, mineral oil, cetyl alcohol and propylene glycol. However, U.S. Pat. Nos. 4,160,823; 4,436,722; 4,269,824 and 4,421,740 equate the mono-higher alkyl quaternary ammonium chloride with a di-higher alkyl quaternary ammonium chloride as the effective conditioning agent in their compositions and, therefore, teach away from the instant unique composition which is specific to the di-higher alkyl quaternary ammonium salts because it has been found that the substitution of a mono-higher alkyl quaternary compounds for the di-higher alkyl compounds in the present composition adversely affects the conditioning properties thereof.
However, it is noted that none of the above cited patents discloses a hair conditioner-straightener composition comprising the mixture of a di-higher alkyl quaternary ammonium compound, a C.sub.8 -C.sub.18 amido C.sub.2 -C.sub.3 alkyl di-C.sub.1 -C.sub.2 alkyl amine, a C.sub.14 -C.sub.18 alcohol, mineral oil, cyclomethicone, a hydroxy alkyl cellulose polymer, polyvinyl pyrrolidone and propylene glycol as the essential ingredients emulsified in an aqueous medium.